Today in our environmental science lecture, we'll discuss urban green spaces. A recent study in Melbourne found that parks can reduce local temperatures by up to 4 degrees Celsius during heatwaves. However, the effect depends on tree canopy coverage. Areas with less than 30% canopy showed minimal cooling. Interestingly, small pocket parks, if well-shaded, performed better than large open lawns. The researchers also noted that water features, like fountains, contributed to cooling but required significant energy. Therefore, they recommend prioritizing tree planting over other features in city planning.